Megan Fox has separated from her husband Brian Austin Green after 15 years together.

The 46-year-old Beverly Hills, 90210 actor has spoken out to confirm the split from the 34-year-old Transformers actress, and went on to address rumours about her and rapper Machine Gun Kelly, insisting they are just friends.

Green explained on his podcast …With Brian Austin Green that the couple had made the decision to “separate for a little bit” towards the end of last year.

He explained that he and Fox – with whom he shares three children – have been "trying to sort of be apart" since she returned from working away on a film last autumn.

Megan Fox and Brian Austin Green pictured together in December 2019. (Getty Images)

Green said: “I gave her a few weeks, I figured you know, she's been out of the country, she's jet-lagged, she's been shooting nights, I have to give her some time to recoup a little bit and get back into life...

“She said, ‘You know, I realised while I was out of the country working alone that I feel more like myself, and I liked myself better during that experience, and I think that may be something worth trying for me.’

“I was shocked and I was upset about it, but I can't be upset at her, and I wasn't upset at her because that's, she didn't ask to feel that way, it wasn't a choice she made, that's the way she honestly felt.”

Last autumn Fox was working on the film Midnight in the Switchgrass with 30-year-old rapper Machine Gun Kelly, whose real name is Colson Baker.

Green said: “She met this guy, Colson, on set. I've never met him. Megan and I have talked about him. They're just friends at this point.”

Machine Gun Kelly has become close to Megan Fox after they worked on a film last autumn. (AP)

He added: “I trust her judgment, she's always had really good judgment. I don't want people to think her or he are villains or that I was a victim in any way.”

Green and Fox met in 2004 on the set of sitcom Hope & Faith when she was just 18 and he was 30. They became engaged in 2006 and have been married for 10 years.